Manifoled tank cars for unit train service

ABSTRACT

A railway train includes a plurality of interconnected tank cars, each car comprising a tank provided with two lading conduits in the top thereof extending thereinto for communication with the interior thereof and each having an outer end extending above the tank and toward the adjacent end thereof, the lading conduits of adjacent cars being interconnected by flexible connecting conduits; valve assemblies may be connected in each lading conduit inside or outside the tank and are preferably all pneumatically operable from a single location, with external valves being disposed in protective housings; one lading conduit may terminate near the bottom of the tank for filling and/or eduction unloading thereof with the other lading conduit terminating near the top of the tank for venting and filling of an adjacent tank thereof and for automatically determining the outage of the tank. Additional embodiments provide lading ports at the ends of the tank on the longitudinal axis thereof or a conduit mounted above the tank and extending the length thereof and valved to accommodate series or parallel loading of the tank cars.

United States Patent Hurst et al. 1 Aug. 5, 1975 {5 1 MANIFOLED TANK CARS FoR UNIT 3,675,670 7/1972 Ogawa 137/1 TRAIN SERVICE 3,722,556 3/1973 .leffers et al. l4l/23l [75] Inventors: Doug Hurst, Montreal W, Canada; FOREIGN PATENTS OR APPLICATIONS Erling Mowatt-Larssen. Warren, 854,114 1/1940 France 141/35 Ohio [73] Assignee: General American Transportation Primary Emmmerld.louston's' l' Corporation Chicago "L Attorney, Agent, or F1rmPrangley, Dithmar, Vogel,

Sandler & Stotland [22] Filed: Oct. 5, 1973 21 Appl. No.: 403,828 [571 ABSTRACT A railway train includes a plurality of interconnected Relaed Apphcalon Dam tank cars, each car comprising a tank provided with i 1 cominudlion-in-pfln of 561 N0 1 two lading conduits in the top thereof extending there- |97l\ ahandonedinto for communication with the interior thereof and each having an outer end extending above the tank Cl 141/98; 137/575 and toward the adjacent end thereof, the lading con- [5 1] Int. Cl B67b 3/04 duits f adjacent Cars being interconnected by fl ibl [58] Field Search 98, 347, connecting conduits; valve assemblies may be conl4l/l' 2321 2L 1001 99, nected in each lading conduit inside or outside the 2361 23124212431 385-387; 285/971 tank and are preferably all pneumatically operable 367; 222/; 213/76; 6H); 5/3581 from a single location, with external valves being dis- 277/343? 17/261 575i 2l4/l7 posed in protective housings; one lading conduit may A terminate near the bottom of the tank for filling and- /or eduction unloading thereof with the other lading References Cited conduit terminating near the top of the tank for vent- UNITED STATES PATENTS ing and filling of an adjacent tank thereof and for au- 2.1o2,124 12/1937 Lithgow 105/360 Omatimlly determining the Outage 0f the tank- Addi- 2,513,450 7/1950 Carlisle IDS/360 tional embodiments provide lading ports at the ends of 2,603,070 7/1952 Gilmore 137/263 the tank on the longitudinal axis thereof or a conduit 2,670,889 3/1954 Heckendorf. 141/35 mounted above the tank and extending the length 2979-037 4/1961 Yogi ll/232 thereof and valved to accommodate series or parallel 3,353,549 ll/l9fi7 Walker l4l/35 loading of the tank Cars 3.557.708 [/1971 Bolte 105/360 3,664,386 5/1972 Wenzel 141/231 48 Claims, 26 Drawing Figures PATENTEB MN? 51975 0mm QONM SHEET PATENTED AUG 51975 MW l NR kn wmn Rm mm nnn eon 2 2m m JR 3 8m 9m 5 m r LW m em 9% own 9% Non no \wm wm on mum mam mvm mvm mom i'r vm \ELLNI M 1 ..L nvm a V .F. L K Y mwn mm? kw nmm\ T Rm m n non own Rn Rm bwm/ Rm eon 2 mm. mm kwm 9% mm, own own MANIFOLED TANK CARS FOR UNIT TRAIN SERVICE CROSS REFERENCE TO RELATED APPLICATION This application is a continuation-in-part of our copending application Ser. No. [86,846, filed Oct. 6, 1971, now abandoned, and entitled MANIFOLDED TANK CARS FOR UNIT TRAIN SERVICE.

BACKGROUND OF THE INVENTION The present invention relates to railway tank cars and, in particular, to manifolded tank cars which may be interconnected to accommodate loading or unloading of the entire group of interconnected cars without movement thereof from a single point therealong, thereby accommodating consecutive loading, transporting and unloading of fluid ladings and facilitating the formation of unit trains.

The concept of providing fluid communication among a series of interconnected railway tank cars is disclosed in the prior art but previous systems have failed to provide an intertank connection arrangement which insured safe handling of the fluid ladings during transportation. For example, US. Pat. No. l,542,l l6, issued to R, Welcker, discloses railway tank cars for interconnection in a manifolded arrangement to accommodate continuous emptying of the interconnected tanks from a single location, without moving or disconnecting the cars. However, Welckers arrangement does not provide for continuous loading of the interconnected tanks from a single location, and the intertank lading connections are along the longitudinal axes of the tanks which has been found to be a disadvantageous arrangement. Furthermore, Welcker provides exposed valves for controlling the fluid lading flow, which valves must be individually manually operated.

U.S. Pat. No. 3,722,556, issued to William Jeffers et al., discloses a manifolded tank car arrangement which accommodates both loading and unloading of a string of interconnected tank cars from a single location, but .Ieffers et al. provide the intertank lading connections at the bottoms of the tanks, and, in addition, they provide exposed and unprotected lading flow control valves, whereby to present a substantial safety hazard during transit of the tank car. Further, .Ieffers et al. do not provide a lading conduit which during loading automatically determines the final outage of the lading in the tank, a feature which is critically necessary with certain bulk lading commodities to accommodate product expansion in transit.

SUMMARY OF THE INVENTION The present invention provides a railway tank car for unit train service which permits a train of such cars to be loaded or unloaded without movement thereof from a single location, and accommodates consecutive loading, transportation and unloading of liquid ladings all in safety and with improved economy of time and manpower.

It is an important object of the present invention to provide a tank car of the character described, which includes a tank having two lading conduits respectively coupled thereto adjacent to the opposite ends thereof in fluid communication therewith and each extending outwardly from adjacent to the top thereof, and conduit coupling means on each of the lading conduits for coupling at the top of the tank to an adjacent end of an associated flexible connecting conduit to place the tank in fluid communication with the tanks of adjacent like tank cars.

In connection with the foregoing object, it is another object of this invention to provide a railway tank car of the type set forth, wherein the lading conduit serving as the output conduit during loading has the inner end thereof extending into the tank and terminating a predetermined distance below the top of the tank, thereby automatically to control the level to which the tank may be filled and thereby to determine the volume of free vapor space at the top of the tank.

It is another object of this invention to provide a rail way tank car of the type set forth, wherein the inner end of the other lading conduit terminates closely adjacent to the bottom of the tank to facilitate emptying of the tank through said conduit.

Still another object of this invention is to provide a railway tank car which includes a tank having two lading conduits coupled thereto and in fluid communication therewith, two valves respectively connected in the lading conduits for controlling the flow of the liquid lading therethrough, and valve control mechanism cou' pled to each of the valves and actuatable from a single location automatically to operate the valves,

Yet another object of this invention is to provide a railway tank car which includes a tank having lading conduits and valves of the character described, wherein the valves are disposed externally of the tank at the top thereof, and further including guard structure mounted on the tank and cooperating therewith substantially to surround the valves for protection thereof.

It is another object of this invention to provide a railway tank car including a tank having a main lading conduit disposed thereabove and extending longitudinally thereof substantially the entire length thereof, two branch lading conduits communicating with the main conduit and being respectively coupled to the tank at the top thereof and in communication with the interior thereof, and a valve assembly connected in the main conduit intermediate the two branch conduits and hav ing an open condition permitting passage of fluid lading through the main conduit for connecting adjacent tank cars in parallel to accommodate simultaneous loading thereof and a closed condition preventing passage of fluid lading through the main conduit and for connecting adjacent tank cars in series to accommodate serial loading thereof.

In connection with the foregoing object, it is another object of the invention to provide a railway tank car of the type set forth, wherein a vent line is disposed above the tank and extends longitudinally thereof substantially the entire length of the tank and has a connection in fluid communication with the tank, the vent line also having a check valve in the connection to the tank closing automatically when the lading in the tank reaches the proper level during loading.

It is another object of this invention to provide a railway tank car which includes wheeled chassis structure provided with chassis coupling means movable between coupling and uncoupling conditions, a coupling control member connected to the chassis coupling means and movable from a coupling to an uncoupling configuration for effecting movement of the chassis coupling means to the uncoupled condition thereof, and lock mechanism engageable with the coupling control member in the coupling configuration thereof for preventing movement thereof to the uncoupling configuration thereof.

Still another object of this invention is to provide a railway train comprising a plurality of tank cars according to the present invention connected in tandem relationship.

A still further object of the invention is to provide a railway train of the type set forth wherein at least the end tank cars have a loading and unloading assembly at the bottom thereof for connection to a source of lading or for connection to an outlet pipe for loading and unloading the train of tank cars serially therethrough.

Still another object of the invention is to provide a railway train of the type set forth wherein at least one of the tank cars is loaded with an inert gas under high pressure, connection of the gas under high pressure to the tank cars carrying lading serving to cause the gas to push the Iading from the tank cars in the train to unload the same.

Further features of the invention pertain to the particular arrangement of the parts of the railway tank cars and railway trains whereby the above-outlined and additional operating features thereof are attained.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. I is a side elevational view of a railway train comprising three railway tank cars constructed in accordance with and embodying the features of a first embodiment of the present invention;

FIG. 2 is an enlarged side elevational view of one of the tank cars illustrated in FIG. I;

FIG. 3 is an end elevational view of the tank car of FIG. 2, as viewed from the right-hand end thereof;

FIG. 4 is a further enlarged fragmentary side elevational view in partial vertical section of the interconnected ends of two adjacent ones of the tank cars of FIG. 1;

FIG. 5 is a fragmentary top plan view of the interconnected tank car ends illustrated in FIG. 4;

FIG. 6 is a still further enlarged fragmentary view in vertical section taken along the lines 66 in FIG. 5, and illustrating the lading eduction conduit and valve assembly of the tank car;

FIG. 7 is a still further enlarged fragmentary view in vertical section of the lading vent conduit and valve assembly of FIG. 5, taken along the lines 77 in FIG. 5;

FIGS. 7A and 7B are similar to FIG. 7 and show two other embodiments of a lading vent conduit useful in the present invention;

FIG. 8 is a fragmentary end elevational view of the uncoupling rod locking assembly of the present invention, showing the uncoupling rod locked in the coupling configuration thereof;

FIG. 9 is a fragmentary top plan view of the uncoupling rod locking assembly of FIG. 8;

FIG. 10 is a side elevational view in partial section of the uncoupling rod locking assembly of FIG. 8, as viewed from the left-hand side thereof, and with the uncoupling configuration of the uncoupling rod illustrated in broken line;

FIG. 11 is a further enlarged fragmentary side elevational view of the uncoupling rod locking assembly as illustrated in FIG. 10, with the unlocking position of the lock member illustrated in broken line;

FIG. 12 is a side elevational view of a railway train comprising three railway tank cars constructed in accordance with and embodying the features ofa second embodiment of the present invention;

FIG. 13 is an enlarged side elevational view of one of the tank cars illustrated in FIG. 12, with portions of the tank broken away to more clearly show the inputoutput conduit structure;

FIG. 14 is a fragmentary end elevational view of the tank car of FIG. 13, as viewed from the righbhand end thereof;

FIG. 15 is a further enlarged fragmentary side elevational view in partial vertical section of the interconnected ends of two railway tank cars constructed in accordance with and embodying the features of a third embodiment of the present invention;

FIG. 16 is a side elevational view of two interconnected railway tank cars constructed in accordance with and embodying the features of a fourth embodiment of the present invention;

FIG. 17 is an enlarged fragmentary side elevational view of a valve mechanism in the lading conduit of one of the railway cars of FIG. I6;

FIG. 18 is an end elevational view of the valve mechanism of FIG. 17, as viewed from the right-hand end thereof;

FIG. 19 is a fragmentary top plan view of one of the tank cars shown in FIG. 16, illustrating the bend in the lading conduit to accommodate the tank manway;

FIG. 19A is an enlarged partial cross-sectional view as seen in the direction of the arrows along the line l9Al9A in FIG. 16;

FIG. 20 is an enlarged fragmentary view in vertical section of the interconnected ends of two railway tank cars constructed in accordance with and embodying the features of a fifth embodiment of the present invention;

FIG. 21 is a fragmentary view in vertical section taken along the line 2l-2l in FIG. 20, and illustrating the support structure for the lading conduit;

FIG. 22 is a fragmentary view in vertical section of a portion of a railway tank car, showing an alternative embodiment of the tank shell and lower conduit assembly of the tank car of FIG. 20', and

FIG. 23 is a fragmentary view in vertical section showing an alternative embodiment of the lower conduit assembly illustrated in FIG. 20.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring now to FIGS. I through 7 of the drawings, there is illustrated a railway train, generally designated by the numeral 50, comprising three railway tank cars, each generally designated by the numeral 60. Each of the tank cars 60 includes a pair of trucks respectively disposed at the opposite ends thereof and each provided with pairs of rail wheels for rolling engagement with the rails of the standard railway track 55. Each tank car 60 is further provided with a coupler at each end thereof for coupling adjacent tank cars together in tandem relationship. Mounted on each of the truck assemblies 70 is a longitudinally extending center sill and an arcuate saddle bolster for supporting thereon one end of an associated tank, generally designated by the numeral 500, all in a well known manner.

The tank 500 includes a tank body 50! comprising a generally cylindrical inner side wall or shell 503 with the longitudinal axis thereof disposed in use substantially horizontally, the shell 503 being surrounded by a concentric cylindrical outer jacket 504 spaced radially a predetermined dlnance from the shell 503 and cooperatin therewith to define an insulation space which may he flllQt with suitable insulation material 506. The opposite ends of the tank body 501 are closed by generlv d me shaped tank heads 505 for defining a coml ltftelv enclosed liquid lading compartment. Formed in me a .n of the cylindrical tank body 50] substantially midv. .iy between the ends thereof is a cylindrical manway 597 extending substantially vertically upwardly from the tank body 501 and closed at the upper end .erwf by a manway cover 509. Connected to the bottom of the tank body 501 generally midway between the ends thereof is a loading or unloading assembly, generally designated by the numeral 510, and including a fitting 51] mounted in a complementary opening in the tank body 50! and coupled through a valve 512 to a short loading pipe 513 which extends vertically downwardly from the fitting 511 and terminates in a lower end which is closed by a cap 514.

Mounted on the top of the tank 500 is a liquid lading level detector, generally designated by the numeral 515, and including a pipe 516 projecting downwardly into the tank and housing a sensor, which is preferably electronic and may include a thermistor, which sensor is electrically connected to an electrical socket 517 located adjacent to the bottom of the tank, the lower end of the pipe 516 being closed by a cap 518. When in use, suitable indicating means may be plugged into the socket 517 for indicating the readings made by the liquid level detector 515.

The tank 500 is also provided with a lading vent conduit, generally designated by the numeral 520, disposed adjacent to one end of the tank 500 and a lading eduction conduit, generally designated by the numeral 520A, disposed adjacent to the other end of the tank 500. In use during loading, the eduction conduit 520A is the input to the tank 500 and the vent conduit 520 is the output from the tank 500, while during unloading the vent conduit 520 is the input to the tank 500 and the eduction conduit 520A serves as the outlet or eduction conduit for the tank 500. Referring in particular to FIGS. 4 through 7 of the drawings, the vent conduit 520 includes a cylindrical pipe 521 extending inwardly through a complementary opening in the top of the tank body 50] having an annular mounting flange 523 at the outer end thereof for connection to the outer surface of the tank shell 503 as by welding for mounting the pipe 521 in place. Preferably, the inner end 522 of the pipe 521 is flared outwardly and downwardly to accommodate increased rate of loading of the tank 500, and terminates a predetermined relatively short distance below the top of the tank shell 503 for a purpose to be explained more fully hereinafter.

Mounted immediately above the flange 523 is a valve, generally designated by the numeral 530, the details of which will be described more fully below, the valve 530 having mounted immediately thereabove a tubular elbow 525 curving upwardly and outwardly toward the adjacent end of the tank 500. The elbow 525 is provided at the lower end thereof with an annular mounting flange 526 for attachment to the mounting flange 523 with the valve 530 disposed therebetween, while the upper end of the elbow 525 is secured by suitable means, such as welding, to a horizontal cylindrical pipe section 527 which terminates between the associated valve 530 and the domed tank head 505 at the adjacent end of the tank. Referring to FIGS. 5 and 7, it will be seen that the flange 526 has six cutouts around the periphery thereof, whereby six bolts 528 are provided that extend through openings in the flange 526 to connect the same to the flange 523, while there are six additional bolts 528A that interconnect the upper valve flange 532 directly to the mounting flange 523; as a consequence, there are 12 bolts connecting the valve 530 to the mounting flange 523, whereas there are only six bolts connecting the flange 526 to the flange 523. Therefore, in the case of injury to the assembly due to force being applied to the elbow 525 such as in a derailment, overturn or the like, the connection between the elbow 525 and the valve 530 will be broken, whereas the additional six bolts 529 would retain the valve 530 in operative association with the mounting flange S23 and the opening to the vent pipe 521.

The eduction conduit 520A (see FIGS. 5 and 6) includes an eduction pipe 521A extending vertically downwardly into the tank 500 and provided at the upper end thereof with an annular mounting flange 523A secured as by welding to the outer surface of the tank shell 503 for mounting the eduction pipe 521A in place The inner end 522A of the eduction pipe 521A is downwardly and outwardly flared to permit place ment of the lower end thereof close to the bottom of the shell 503 so as substantially completely to unload the tank therethrough. By providing a flared lower end 522A, it is possible to place the lower periphery thereof very close to the shell 503 and still maintain a total flow area between the lower end 522A and the shell 503 that is essentially equal to the internal area of the eduction pipe 521A. The outward flaring of the inner end 522A also accommodates an increased rate of unload ing and during loading minimizes foaming frothing or severe agitation of the lading. Disposed immediately above the mounting flange 523A and concentric therewith is another of the valves 530.

Mounted immediately above the valve 530 is an elbow 525A identical in construction to the elbow 525, and extending upwardly and outwardly toward the adjacent end of the tank 500. The elbow 525A is provided at the lower end thereof with an annular mounting flange 526A for attachment to the mounting flange 523A with the valve 530 disposed therebetween and is secured at the upper end thereof, as by welding. to a short horizontal pipe section 527A. Referring to FIGS. 5 and 6, it will be seen that the flange 526A has six cutouts around the periphery thereof, whereby six bolts 528 are provided that extend through openings in the flange 526A to connect the same to the flange 523A, while there are six additional bolts 528A that interconnect the upper valve flange 532 directly to the mounting flange 523A; as a consequence, there are twelve bolts connecting the valve 530 to the mounting flange 523A, whereas there are only six bolts connecting the flange 526A to the flange 523A. Therefore, in the case of injury to the assembly due to force being applied to the elbow 525A such as in a wreck or the like. the connection between the elbow 525A and the valve 530 will be broken, whereas the additional six bolts 528A would retain the valve 530 in operative association with the mounting flange 523A and the opening to the eduction pipe 521A.

Disposed in concentric surrounding relationship with the horizontal pipe section 527A and secured thereto as by welding is a cylindrical male sub 566 of a pipe connection generally designated by the numeral 565, the pipe connection 565 also including an internally threaded nut 568 rotatable with respect to the male sub 566 but trapped in place thereon by mating flanges in a well known manner. The nut S68 terminates at a point between the associated valve 530 and the domed tank head 505 at the adjacent end of the tank 500.

It will be appreciated that the pipe connection 565 is of the quick-connect" and quick-disconnect" type. Other quick-connect pipe connections may be used in place of that illustrated at 565. For example, the QuikCon" connector offered by the FMC Corporation or the C-L" coupling offered by Camlock Flange Sales Corp., or the Flange Mate" closures offered by Continental-Emsco Co. may be used in place of the quick-connect pipe connection 565 illustrated.

The valves 530 which are respectively connected in the vent and eduction conduits 520 and 520A are identical in construction, whereby only one of the valves S30, associated with the eduction conduit 520A, will be described in detail. Referring in particular to FIGS. 6 and 7 of the drawings, the valve 530 includes a cylindri cal valve body 531 disposed coaxially with the eduction pipe 521A and provided at the upper and lower ends thereof with annular mounting flanges 532 which are respectively separated from the output pipe flange 523A and the elbow flange 526A by suitable gaskets 534. Preferably, flanges 523A, 526A and 532 are all provided with complementary openings therethrough spaced circumferentially therearound for receiving the complementary bolts 528 and 528A securely to assemble the output pipe 521A, the valve 530 and the elbow 525A in a fluid-tight connection, all as has been described hcreinabove.

Preferably, the valve 530 is of the type commonly known as a butterfly valve which is provided with a circular disk (not shown) disposed within the valve body 531 for movement between a closed position blocking the flow of fluid through the valve body 531 and an open condition accommodating passage of fluid therethrough. Valves of this type are disclosed in the US. Pat. Nos. 2,740,423 and 2,994,342 issued to C. K. Stillwagon and in the US. Pat. No. 3,241,806 issued to A. H. Snell, Jr. The valve 530 includes a rotatable stem 537 projecting laterally from the valve body 531 and connected to the circular disk therein for effecting rotational movement thereof between the open and closed positions thereof. Mounted on the stem 537 is a valve position indicator 539 visible from the exterior of the car to show the position of the valve and also useful as a handle for manual actuation of the valve 530.

Preferably, the valve 530 is also automatically operable and to that end includes a valve actuator mechanism, generally designated by the numeral 535, which includes a piston disposed within a cylinder 538 and threadedly engageable with the valve stem 537 so that reciprocating movement of the piston will effect a corresponding rotational movement of the valve stem 537. A bias spring within the cylinder 538 resiliently urges the piston and the valve stem 537 to a closed condition, whereby the valve 530 is normally closed. The valve actuator 535 may be electrically or pneumatically operated. but in the preferred embodiment of the invention it is illustrated as being pneumatically operated, whereby the actuator 535 includes an air hose coupling for coupling the actuator 535 to an air actuation system, generally designated by the numeral 540. The

valve position indicator 539 can be used as a manual override of the automatic system described. The valves 530 are preferably both disposed on the same side of the tank 500, but it will be appreciated that other arrangements could be used.

The air actuation system 540 includes a network of air conduits, including a main conduit 543 extending longitudinally along one side of the tank 500 adjacent to the top thereof and externally thereof, the main line 543 being connected by a short branch line 541 to the valve actuator 535 of the input conduit 520 and being connected by a branch line 542 to the valve actuator 535 of the output conduit 520A. At the opposite ends of the tank 500, the main line 543 is connected respectively to two tank head lines 545 which extend outwardly over the adjacent head ends 505 of the tank and are in turn respectively connected to Y-couplers 546. Each of the Y-couplers 546 is in turn connected by a chassis line 547 to the pneumatic system of the tank car and by a line 548 to an inter-tank connecting line 549 which is in turn connected to the air actuation system 540 of the next adjacent tank car, each of the lines 548 having a release valve 549A therein. Thus, it will be understood that compressed air may be fed to the air actuation system 540 of all of the interconnected tanks 500 in a train of the tank cars 60 simultaneously by operation of the central pneumatic system of the train from a single location.

Each of the valves 530 is disposed in a protective housing or guard structure. generally designated by the numeral 550, the protective housings 550 each being identical in construction. whereby only one of these housings will be described in detail. Referring in particular to FIGS. 5 through 7 of the drawings, the protective housing 550 includes a pair of arcuate weld pads 55] respectively disposed forwardly and rearwardly of the associated valve 530 and extending transversely of the tank shell 503 and fixedly secured to the outer surface thereof as by welding.

Respectively mounted on the weld pads 551 are two guard plates 552 which are constructed substantially as mirror images of each other, each of the guard plates 552 preferably being constructed of steel plates which is substantially thicker than the tank shell 503 and is fixedly secured to the associated weld pad 551 as by welding. Each of the guard plates 552 is generally rectangular in shape but has an arcuate bottom edge complementary to the weld pad 551, the guard plates S52 extending vertically upwardly from the tank shell 503 and transversely thereof and at opposite ends of the valve 530 closely adjacent thereto and substantially parallel to each other. Each of the guard plates 552 is further connected to the associated weld plate 551 by a gusset plate 553 disposed approximately midway between the opposite side edges of the guard plate 552 and extending therefrom away from the valve 530. Fixedly secured to the outer surfaces of each of the guard plates 552 is at an angle iron 554 which serves to connect the guard plate 552 to the adjacent edge of the tank jacket 504, which jacket is cut away to accommodate the valve 530. The guard plates 552 protect the valves 530 from physical damage, such as for example in a roll-over" of the tank car 500.

In order to provide protection from the weather for the valves 530, a pair of parallel housing end walls 557 respectively are disposed outwardly of the guard plates 552 and parallel thereto, and a pair of side walls 558 respectively are disposed substantially perpendicular to the end walls 557 and extending therebetween. The end walls 557 and side walls 558 are all provided with inturned flanges at the upper ends thereof to receive a rectangular cover plate 555 held in place by screws 559 and provided with a complementary opening therethrough for accommodating the elbow 525 (or 525A), the cover plate 555 cooperating with the end walls 557 and the side walls 558 and the tank shell 503 and jacket 504 substantially to surround the associated valve 530 to provide a weather protective enclosure therefor. The plates 552 prevent damage to the valve 530 in the event of an accidental derailment and overturning of the tank car or inadvertent contact with objects along the track.

The vent conduit 520 of one tank 500 is connected to the eduction conduit 520A of an adjacent tank 500 by means of a flexible connecting conduit, generally designated by the numeral 560. The conduit 560 includes a flexible tubular hose 561 provided at the opposite ends thereof with annular coupling flanges 562, at least one of which is complementary to the connecting flange 529 on the vent conduit 520 for coupling thereto by means of bolts in the usual manner. It will be understood that other flexible" connections may be used in place of the conduit 560, other conduit interconnecting means being acceptable so long as they accommodate all of the relative movements between two coupled tank cars in train action.

Connected to the end flange 562 at the other end of the hose 561 by bolts is the coupling flange 564 of a coupler extension pipe 563. Disposed on concentric surrounding relationship with the coupler extension pipe 563 and secured thereto as by welding is a female sub 567 of the pipe connection 565, adapted for mating with the male sub 566 on the eduction conduit 520A of an adjacent tank 500, the female sub 567 being externally threaded for threaded engagement with the nut 568 securely to join the male and female subs 566 and 567 in a fluid-tight joint thereby to place the adjacent tanks 500 in fluid communication with each other. It will be appreciated that the pipe connection 565 affords a quick and simple means for connecting and disconnecting the flexible conduit 560 to a tank 500. Preferably, the flexible connecting conduit 560 will be more or less permanently connected to the coupling flange 529 of the vent conduit 520 of the tank car 60, with the opposite end of the conduit 560 carrying the female sub 567 being free for connection to the eduction conduit 520A of an adjacent car by means of a pipe connection 565. The flexible connecting conduit 560 is of such a length as to afford considerable slack when coupled to an adjacent tank car in use.

In order to permit complete emptying of the flexible connecting conduits 560 subsequent to loading of the tank car train 50 and prior to transport thereof, there has been provided a conduit support 600 between each pair of railway tank cars 60, the support 600 being best illustrated in FIGS. 1, 4 and 5 of the drawings. As illustrated, the adjacent ends of the tanks 500 have mounted adjacent to the upper sides thereof and displaced slightly from the centerline thereof (see FIG. 5) a lug 601 carrying a set of pivotal links 602. One of the set of links 602 has threadingly connected thereto a threaded sleeve 603 carrying at the outer end thereof a hook 604. Connected between the hook 604 and the other set of links 602 is a wire rope 605. Disposed about the midpoint of the flexible connecting conduit 560 is a clamp 610 from which extends a strut 612 connected to a sleeve 611 slidably receiving the wire rope 605 therethrough. The tension in the wire rope 605 can be adjusted by means of a ratchet 606 drivingly engaging the threaded sleeve 603, the ratchet 606 carrying a handle 607 that a user can grasp to operate the ratchet 606 so as to turn the threaded sleeve 603 to tighten the wire rope 605 as required. There further is provided a bracket 608 on the tank 500 adjacent to the handle 607 and a cooperating chain 609 to hold the handle 607 in the adjusted position.

The conduit support 600 can be adjusted by means of the ratchet 606 so as to hold the clamp 610 and the associated center of the flexible connecting conduit 560 at an elevation slightly above that of the associated pipes 527 and 563 so as to permit complete drainage of the conduit 560 at the completion of a loading oper ation and prior to transport of the tank 500, all as will be explained more fully hereinafter.

Referring to FIG. 7A of the drawings, there is shown a modified form of adjustable vent conduit in place of the fixed inner end 522 of the pipe 521, whereby to provide for adjustability of the outage of the associated tank car. As illustrated, a movable pipe section 700 is provided around the lower end of the vent pipe 521, a suitable packing 701 being provided therebetween to afford a fluid-tight seal. Extending outwardly from the pipe section 700 is a pair of arms 702, the outer ends of which are apertured to receive therethrough the lower ends of adjusting bolts 705. The lower end of the adjusting bolt carries a nut 706 and the upper end of the adjusting bolt extends through the tank shell 503 and terminates in an outer end 707 which is shaped to receive a tool for turning the bolt 705. At the place where the bolt 705 passes through the shell 503, a packing gland 710 is provided including a housing 7] l welded to the shell 503 as at 712. A nut 713 closes the upper end of the packing gland 710 to maintain the packing 714 in position. Finally, there is provided a pin 715 which limits the distance that the movable pipe section 700 can be moved upwardly, thereby to set the minimum outage that can be accomplished by adjustment of the vent conduit.

It will be appreciated that the outage provided by the vent 520 using the adjustable pipe section 700 can be adjusted from outside of the tank car 500 by threading the bolts upwardly and downwardly, thus to position the pipe section 700 higher or lower with respect to the top of the tank shell 503. The higher the position of the pipe section 700, the less the outage, the minimum outage permitted by the system being determined by the position of the pins 715. Increased outage can be obtained by threading the bolts 705 to move the pipe section 700 downwardly.

Referring to FIG. 7B of the drawings, there is shown yet another form of the adjustable vent, this form requiring access to the interior of the tank in order to adjust the position of the movable pipe section and therefore the outage. Where appropriate like reference numerals have been applied as in H0. 7A but with the addition of the suffix "B". The bolts 7058 instead of passing through the shell 503 terminate in pads 708B welded to the interior of the shell 503. An additional nut 70913 is provided on each bolt 7058 and engages the upper surface of the associated arm 702B, whereby positively to position the arm 7028. It will be appreciated therefore, that the outage provided by the structure of FIG. 78 can also be adjusted to provide more or less outage as required.

Referring now also to FIGS. 8 through 11 of the drawings, there is illustrated an uncoupling rod locking mechanism, generally designated by the numeral 570, for preventing inadvertent or accidental uncoupling of two adjacent tank cars 60, the tanks 500 of which are in fluid communication with each other through the flexible connecting conduit 560. Each end of the tank car 560 is provided with a service ramp or catwalk 57] disposed horizontally adjacent to the bottom of a tank 500, the catwalk S7l having secured thereto a hand rail 569 and a side rail 579 and one or more vertically aligned steps 572 to facilitate mounting of the catwalk by a trainmen. As is best illustrated in FIGS. 8 and ll) of the drawings. the step 572 is preferably a metal band bent into a substantially rectangular configuration and secured to the underside of the catwalk 57] along the side thereof.

Fixedly secured to the endmost side of the step 572 is one end of an elongated angle iron 574 extending substantially perpendicular to the step 572 along the adjacent end of the tank car transversely thereof. The angle iron 574 is an upstanding attachment flange 576 and a horizontal flange 575, one end of the attachment being fixedly secured to the step 572 by a suitable fas tener, and the other end thereof being secured to a mounting plate or bracket S73 suspended from the catwalk 57!. Fixedly secured to the underside of the horizontal flange 575 at longitudinally spaced apart points thereon and depending therefrom are two support brackets 577 provided with generally U-shaped lower ends 587 for receiving therein an uncoupling rod, generally designated by the numeral 580. Formed in the horizontal flange 575 between the support brackets 577 is an opening surrounded by a tubular sleeve 578 having an opening of square cross section therein and secured to the upper surface of the horizontal flange 575.

The uncoupling rod 580 is an elongated integral rod having a handle portion 581 extending downwardly below the support brackets 577, the remainder of the uncoupling rod 580 defining an elongated U-shaped member extending substantially perpendicularly to the handle 581 and including a pair of elongated leg portions 582 and 583 interconnected at the ends thereof remote from said handle 58! by a bight portion 584.

In use, the connecting rod 580 is disposed with the leg portion 583 thereof resting in the U-shaped lower ends 587 of the support brackets 577, these U-shaped ends 587 serving as bearings to facilitate rotational movement of the uncoupling rod 580 about the longitudinal axis of the leg portion 583. Encircling the leg portions 582 and 583 of the uncoupling rod 580 and fixedly secured thereto is a loop portion 586 at one end of a connecting rod 585, the other end of which is connected to the coupler 80 at the adjacent end of the tank car 60. In use, the coupler rod 581 is manually movable by means of the handle portion 581 between a coupling configuration illustrated in solid lines in FIGS. 8 through 11, and an uncoupling configuration, illustrated in broken lines in FIGS. 10 and 11. movement of said uncoupling rod 580 from the coupling to the un coupling configuration thereof effecting movement of the coupler 80 to an uncoupling condition by means of the connecting rod 585 for uncoupling the adjacent tank car 60.

It is important to insure that the uncoupling rod 580 is not inadvertently or accidentally moved to the un coupling configuration thereof when two adjacent tank cars are in fluid communication with each other because this might result in a rupture of the inter-tank connection through the flexible connecting conduit 560, since neither the conduit 560 nor the conduits 520 nor the conduits 520 or 520A are designed to handle the buff and draft forces of a railway train in transit. Accordingly, there is provided a locking pin, which extends vertically through the sleeve 578 and the adjacent opening in the horizontal flange 575, the pin 590 being of square cross section and provided at the upper end thereof with a handle 591 and being secured at the lower end thereof to a locking tab 592 having a bearing surface 593 thereon. When the locking pin 590 is disposed in the lowered position thereof, illustrated in solid lines in FIGS. 8 through 11, the bearing surface 593 is positioned for engagement with the upper leg portion 582 of the uncoupling rod 580 to prevent movement thereof from the coupling configuration to the uncoupling configuration. In order to uncouple the adjacent tank car 60, it is necessary only to manually raise the locking pin 590 to the unlocking position illustrated in broken lines in FIG. 11, thereby moving the locking tab 592 out of the path of the upper leg portion 582 to permit movement of the uncoupling rod 580 between the coupling and uncoupling configurations thereof. Upon release of the handle 581, the locking tab 592 will rotate when the upper leg 582 contacts the sloping surface 594 pivoting the locking tab 592 out of the way, temporarily to allow the leg 582 to return to its neutral position, whereby the locking tab 592 will then return to its locking position.

In operation, a plurality of the tank cars 60 are coupled together, as illustrated in FIG. 1, with the vent conduit 520 of one car coupled to the eduction conduit 520A of the adjacent car by means of the flexible connecting conduits 560 in the manner described above, thereby to place the tanks 500 of the cars in fluid communication with one another to form a continuous lading vessel. While three of such interconnected railway cars have been illustrated in FIG. 1, it will, of course, be appreciated that the railway train 50 may comprise any desired number of such railway tank cars 60. When it is desired to fill the tanks 500 of the train 50 with fluid lading, the input end of the train 50 is moved into position adjacent to an associated source 40 of liquid lading, which is preferably provided with a sub 567 for connection to the sub 566 at the free end of the connecting conduit 560 attached to the eduction conduit 520A at the adjacent end of the train. The vent conduit 520 at the other end of the train may be vented to atmosphere or may be coupled to a scrubber 30 or other suitable anti-pollution device. The valves 530 on all of the tanks 500 are then simultaneously opened by application of pressurized air to the actuators 535, which can be accomplished from a single remote location, as was described above.

The fluid lading, which is normally a liquid lading, is introduced into the first tank 500 at the right-hand end of the train 550, as illustrated in FIG. 1. When the tank 500 is filled to a predetermined level, the pressure of the vapor therein above the liquid lading will build up and push the liquid lading upwardly through the vent conduit 520 at the other end of the tank and thence through the flexible connecting conduit S60 and into the next adjacent tank 500 through the eduction conduit 520A thereof. When the next tank is filled to a preti teri inerl level. the liquid lading will flow therefrom 'o the next succeeding tank and this process will be continued until all of the tanks 500 in the train 550 nve been filled to the predetermined level with liquid 'mtiing. It will be noted that the entire train of tank car 60 can be filled from a single location without moving any of the tank cars 60 or disconnecting them from one another.

It is a significant feature of the present invention that .he level to which the tank 500 will be filled with liquid lading is predetermined by the distance which the inner end 522 of the vent pipe 521 extends below the top of the tank shell 503. This level is preferably set so that there will be provided a free vapor space or outage above the liquid lading at the top of the tank 500, which vapor space is required in the case of expandable liquid ladings, including flammable liquid ladings. It will be appreciated that when the level 595 of the surface of the liquid lading within the tank 500 reaches the bottom of the vent pipe 522, ti will close the opening therein and prevent further escape of vapors therethrough, after which the remaining vapors at the top of the tank 500 will be compressed as filling of the tank 500 continues The pressure build-up will continue until it is sufficient to force liquid lading through the vent pipe 522 to the next adjacent tank 500. lt will, therefore, be understood that by judiciously selecting the length of the vent pipe 522, the maximum level of liquid lading within the tank and, therefore, the minimum volume of frceboard or outage at the top of the tank will be determined. When the tank car farthest from the source 40 of liquid lading has reached the desired depth of fill, the liquid lading level detector 515 therein is actuated and can be connected to control the pump forcing lading into the tank cars to turn off the pump and thus stop fill at the desired level in the final tank car to be filled. It will be appreciated that the de tectors 515 can be used to monitor the progress of filling along a string of the tanks 500.

After the train 50 of tank cars 60, and specifically the tanks S thereof, have been loaded, it is desirable prior to transport of the train 50 to empty all lading from the flexible connecting conduits 560 between adjacent tanks 500 and also from the other conduits 520 and 520A connected between the conduit S60 and the adjacent valves 530. It will be appreciated that this is desirable so that there will be no lading in the conduits outside of the tanks 500, i.e.. outwardly beyond the valves 530, during transport of the train 50, all for safety reasons. If the lading is flammable or otherwise dangerous. it is desirable to have no lading in these conduits in the event of an accidental rupture of any of the conduits or an accidental separation of the cars 50 and the associated tanks 500 during transport.

In order to remove from the conduits 520, 520A and 560 all liquid lading at the end of a loading operation, in accordance with a first preferred method, a source of high pressure gas is connected to the input end of the train of tank cars, and specifically to the eduction conduit 520A that was connected to the source 40 of liquid lading. The gas pressure will force the liquid lading from the right-handmost conduit 520A and in so doing will push a corresponding quantity of lading upwardly through the vent conduit 520 in the right-handmost car and through the flexible connection 560 and into the adjacent car. the middle car as illustrated in FIG. 1. As soon as the level of liquid in the right-hand-most car falls below the lower end of its vent conduit 520, the air under pressure will force all of the liquid upwardly and out of the vent conduit 520, the associated flexible conduit 560 and that portion of the connected eduction conduit 520A above the liquid level in the adjacent middle tank car. This process will be repeated down the entire string of tank cars until the conduit 520 and the flexible conduit 560 and the portion of the eduction conduit 520A above the liquid level in the left handmost car have been emptied, thus to empty all of the conduits 520, 520A and 560 throughout the entire length of the train 50 in seriatim. It will be appreciated that the liquid level in the last tank car loaded prior to the emptying of the conduits must be such that the last tank car loaded can accept all of the lading from the conduits along the entire length of the train 50.

In a second preferred method of emptying the con duits 520, 520A and 560 along a train of tank cars 60, the eduction conduit 520A that was connected to the supply 40 of liquid lading is closed and the vent conduit 520 that was connected to the scrubber 30 is connected to a source of subatmospheric pressure or vacuum. As a result there will be a pressure differential between the right-handmost eduction conduit 520A in FIG. I and the left-handmost vent conduit 520 just as was the case in the first preferred method described above. As a consequence. there will be a seriatum emptying of the conduits 520, 520A and 560 progressively from the right in FIG. 1 through to the left-hand end of the train 50 in FIG. I. After the pressure in the tanks has fallen to atmospheric pressure, the eduction conduit 520A that was connected to the supply 40 of liquid lading will be vented to atmosphere. It will be seen that in this method also the level of liquid lading in the left handmost car, i.e., the car last loaded, must be low enough so that the car can accept all of the lading from the conduits 520, 520A and 560.

After the train 50 has been completely filled with liquid lading and the conduits 520, 520A and 560 emptied as described above, the valves 530 are closed by shutting off the supply of compressed air thereto, the valves then automatically returning to their normally closed conditions under the urging of the bias springs. As explained above, all of the valves 530 may be simulta neously closed from a common remote location, there being one of such locations at each tank car. The fact that the valves 530 are closed can be verified by visually inspecting the positions of the indicators 539, the indicators 539 being in a horizontal position when the valves 530 are closed and being in a vertical position when the valves 530 are open. The train 50 may then be transported to an unloading station in the usual manner. It is significant feature of the present invention that the conduits 520 and 520A and the flexible connecting conduit 560 are so constructed and arranged as to accommodate all of the various types of movement which a train normally undergoes in transit thereby to facilitate a safe and unencumbered transportation of the train of tank cars 60.

More particularly, in the first preferred embodiment of the invention the outer ends of the conduits S20 and 520A are respectively set back behind the domed heads 505 of the tank ie. each of these conduits terminate at points between the associated protective hous ing 550 and the head 505 at the adjacent end of the tank. This set-back position of the ends of the conduits 520 and 520A permits the flexible connecting conduit 560 to be of a length sufficient to provide a consider able amount of slack between adjacent tanks when the tanks are on a straight portion of track. This slack length in the connecting conduit 560 insures that there will be no undue stresses placed on the flexible conduit 560 or the conduits 520 and 520A as the train undergoes various track conditions such as sharp curves, inclines, banked curves, uneven rails and the like.

Using conventional trucks and a standard overhang as illustrated in FIGS. 1 to 5, it will be appreciated that the necessary slack length in the flexible connecting onduit 560 might not be provided if the conduits S and 520A extend outwardly beyond adjacent ends of the tank 500 because the connecting conduit 560, while being flexible, is of sufficient stiffness to prevent its being bent into a tight curve, whereby the amount of slack which can be provided in the connecting conduit 360 increases with the length thereof. In this regard. the positioning of the conduits 520 and 520A at "*e tops of the tanks 500 permits a length of flexible connecting conduit 560 which would not be permitted in the conduits 520 and 520A were located on the heads 505 of the tank 500.

It will also be observed that the location of the conduits 520 and 520A at the top of the tank 500 minimizes the possibility of lading spillage in the event of an accidental derailment of the train 50 or accidental dis connection of adjacent cars 60. It will also be noted that the possibility of accidental damage to the valves 530 is minimized by the protective guard plates 552 associated with each of the valves 530. More particularly, each of the guard plates 522 is of sufficient thickness and strength as to prevent damage of the valve 530 except in the case of their being subjected to the most severe forces which would be sufficient to destroy the integrity of the tank 500 itself. The protective guard plates 552 are so designed that even in the event of the tank 500 rolling over, the valves 530 would be protected.

After the train 50 has reached its destination, the tanks 500 thereof may be unloaded by connecting the eduction conduit 520A at one end of the train to an associated liquid lading reservoir or other storage facility 40 by suitable connecting means. At this point, the valves 530 of the tanks 500 would all be simultaneously automatically opened by applying compressed air to the valve actuators 535 thereof, which actuation may be accomplished from a common remote location as described above. The tank at the opposite end of the train is pressurized with an appropriate gas as through the vent conduit 520 thereof, whereby the liquid lading therein will be forced upwardly through the eduction pipe 521A and the flexible connecting conduit 560 to the next adjacent tank 500 at the same time the liquid lading will be forced from the tank at the other end of the train into the storage facility, thus to unload serially the entire train of tank cars. This unloading will continue until the first pressurized tank 500 is empty. after which each succeeding tank 500 will in turn be emptied until the entire train has been unloaded. After unloading, the source of gas pressure is withdrawn from the tanks and the pressurized air to the valve actuators 535 is shut off, whereupon the valves 530 all automatically return to their closed conditions. Thus, it will be appreciated that the entire train 50 can be unloaded in a sin gle operation at a single location without movement of the train or disconnection of any of the cars thereof.

Referring again to FIG. 1, there is illustrated an alternative method of filling and emptying the train of tank cars utilizing the loading and unloading assembly 510 at the bottom of the individual tank cars. More specifi cally, during the loading operation, a connection can be made through a pipe 510A from the source 40 ofliquid lading to the assembly 510 of the adjacent tank car 500. Likewise, when unloading the train 50, the source of gas under pressure can be applied through the conduit 520 or the assembly 510 and the line 510A con nected to a suitable receptacle for the lading, thus to unload the train serially.

In yet another method of unloading the train 50 of tank cars 500 one of the tank cars 500, and preferably a tank car at one of the ends of the train 50 is filled with an inert gas such as nitrogen which is pressurized to a high pressure such as 250 psi. When the train reaches the point for unloading, the inert gas is connected to the vent connection 520 of the adjacent railway car carrying lading and the inert gas pressure utilized to force the lading out of the tank cars in the manner de scribed hereinabove.

Referring now to FIGS. 12 through 14 of the drawings, there is illustrated a railway train, generally designated by the numeral 50, comprising three railway tank cars, each generally designated by the numeral 60. Each of the tank cars 60 includes a pair of trucks respectively disposed at the opposite ends thereof and each provided with pairs of rail wheels for rolling engagement with the rails of a standard railway track 55. Each tank car 60 is further provided with a coupler at each end thereof for coupling adjacent tank cars together in tandem relationship. Mounted on each of the truck assemblies 70 is a longitudinally extending center sill and an arcuate saddle bolster for supporting thereon one end of an associated tank, generally designated by the numerai 100, constructed in accordance with a second embodiment of the invention.

The tank includes a generally cylindrical side wall 103 with the longitudinal axis thereof disposed in use substantially horizontally and having the opposite ends thereof respectively closed by generally domeshaped tank heads 105 for defining a completely enclosed liquid lading compartment. Formed in the top of the cylindrical side wall 103 substantially midway be tween the ends thereof is a cylindrical manway 107 extending substantially vertically upwardly from the tank side wall 103 and closed at the upper end thereof by a manway cover 109. Connected to the bottom of the tank side wall 103 generally midway between the ends thereof is a ioading assembly, generally designated by the numeral 110, and including a fitting lll mounted in a complementary opening in the bottom of the side wall 103 and coupled to a short loading pipe 113 which extends vertically downwardly from the fitting 111 and terminates in a lower end which is closed by a cap 114.

Mounted on the bottom of the tank side wall 103 adjacent to the loading assembly is an unloading assembly, generally designated by the numeral 115, and including a valve assembly 116 mounted in a complementary opening in the side wall 103 and provided with a pair of control wheels 117 (one shown) respectively extending laterally outwardly toward the opposite sides of the tank 100. Coupled to the valve assembly 1 16 and extending vertically downwardly therefrom is a short unloading pipe 118 terminating in a lower end which is closed by a cap 119.

The tank 100 is also provided with two identically constructed input-output conduits, each generally designated by the numeral 120, respectively disposed adjacent to the opposite ends of the tank 100. The inputoutput conduits 120 are arranged as mirror images of each other, wherefor only one of the conduits 120 will be described in detail. Referring, in particular, to FIGS. 13 and 14 of the drawings, the input-output conduit 120 includes an adapter fitting 121 having a reduced diameter lower portion 122 received in a complementary opening or port in the top of the tank side wall 103 adjacent to one end thereof, and an enlarged diameter flange 123 disposed above the tank side wall 103 in contact therewith and in surrounding relationship with the associated port. The flange 123 is coupled by suitable bolts to a complementary flange on a short vertically extending pipe section 124, the upper end of which is in turn connected to an elbow 125, which is in turn connected to a horizontally extending conduit section 127 disposed substantially parallel to the longitudinal axis of the tank 100. The outer end of the horizontal section 127 preferably extends a slight distance outwardly beyond the adjacent end of the tank 100 and terminates in an annular attachment flange 129.

The input-output conduits 120 are respectively supported by two identically constructed supports, each generally designated by the numeral 145. Each support 145 includes a pair of half-rings 146 clamped about the outer end of the adjacent horizontal section 127 by suitable means such as bolts, and connected, as by welding, to the upper ends ofa pair of downwardly and outwardly diverging struts 148. Each of the struts 148 preferably comprises an angle iron coupled at the lower end thereof to a foot pad 149 which is secured to the outer surface of the adjacent tank head 105 as by weld- The attachment flange 129 of each or the horizontal sections 127 of the input-output conduits 120 is constructed and arranged complementary to corresponding flanges 151 at the opposite ends of a flexible connecting conduit 150, whereby each of the flanges 129 may be connected, as by nuts and bolts, to the corresponding flange 151 of the flexible conduit 150 for providing a flexible coupling between the input-output conduits 120 of adjacent tank cars 60. [n this manner, a unit train may be formed with the tanks 100 and the input-output conduits 120 of the interconnected manifolded cars 60 cooperating with the flexible connecting conduits 150 to form a continuous lading vessel extending the entire length of the train. The flexible conduits 150 are of such a length as to accommodate the normal maneuvers of a railway train without danger of rupturing the connection formed by the flexible conduits 150.

In operation, a plurality of tank cars 60 are coupled together as illustrated in FIG. 12, with the adjacent input-output conduits of adjoining cars coupled together by flexible connecting conduits 150 in the manner described above. While three of such interconnected railway cars 60 have been illustrated in FIG. 12, it will of course be appreciated that the railway train 50 may comprise any desired number of such railway tank cars 60. When it is desired to fill the tanks 100 of the train 50 with liquid lading, one end of the train 50 is moved into position adjacent to an associated source of liquid lading (not shown). whereupon the free input-output conduit 120 at that end of the train is coupled by suitable means to the source of liquid lading. Preferably, the input-output conduit 120 at the other end of the train is left open and vented to atmosphere.

Referring to FIG. 12, if the left-hand end of the train 50 is coupled to the source of liquid lading, the lading is introduced into the first tank car 60 in the direction of the arrow until the tank of that car is filled. When the tank 100 is full, pressure will build up therein and move the liquid lading upwardly through the inputoutput conduit at the other end of the tank, through the flexible connecting conduit and into the next adjacent tank 100, which will in turn be filled before the liquid lading flows in a similar manner the next succeeding tank. This process continues until the entire train 50, or any desired portion thereof, is tilled. During the filling operation, the air pressure in the tanks 100 is relieved through the input-output conduits 120 to the next adjacent tank and is finally vented to atmosphere through the end conduit 120 at the other end of the train. Alternatively, each tank 100 may be individually equipped with a suitable air vent, in lieu of venting the air through the manifold tank system.

For unloading the tanks 100, the tank cars 60 are positioned, one at a time, over a suitable pit or hopper or other reservoir (not shown) disposed beneath and between the tracks 55. The unloading valve 116 is then opened by operation of the valve control wheel 117 to discharge the contents of the tank 10 into the reservoir. Preferably, each tank 100 is equipped with a vacuum relief valve (not shown) of sufficient capacity to handle air flow into the tank at peak flow during unloading.

An alternative method of unloading the tanks 100 is to connect the unloading valves 116 of the tanks 100 individually to a manifold connected to a pump which will pump the lading to a terminal.

Further, in addition to the loading of the tanks 100 through the input-output conduits 120 as described above, the tanks 100 may alternatively be loaded through the loading assembly 1 10 at the bottom thereof, thereby affording a great deal of flexibility in loading of the railway tank cars 60. It will be appreciated that this novel arrangement permits an entire train of tank cars 60 to be filled from a single point, thereby obviating the expensive and timeconsuming jockeying of the tank cars one at a time into loading position adjacent to the associated source of liquid lading.

An alternative method of loading the tanks 100 is to connect the loading assembly 1 10 of the tanks 100 individually to a manifold connected to a pump which will pump the lading from a source thereof into the tanks 100.

As an important feature of the present invention, it will be noted that the input-output conduits 120 are disposed in elevated positions above the tanks 100, whereby in the event of any accidental rupture of the connection between adjacent cars provided by the flexible connecting conduits 150, for example, as a result of derailment or accidental uncoupling of the cars 60, the possibility of spillage of the liquid lading is minimized. This may be of paramount importance if the lading is a commodity such as bunker C", sewer sludge, etc., which are considered to be highly pollutant.

Referring now to FIG. 15 of the drawings, there is illustrated a second tank embodiment, generally designated by the numeral 200, for use on the tank cars 60. FIG. 15 illustrates portions of two adjoining tank car 

1. A railway tank car adapted for interconnection in fluid communication with associated like tank cars by flexible connecting conduits for accommodating consecutive loading of fluid ladings, said tank car comprising a wheeled chassis structure provided with chassis coupling means for coupling to the chassis of associated like cars, a tank mounted on said chassis structure, two lading conduits respectively coupled to said tank adjacent to the opposite ends thereof in fluid communication therewith and each extending outwardly therefrom adjacent to the top thereof, and conduit coupling means on each of said lading conduits for coupling at the top of said tank to an adjacent end of an associated flexible connecting conduit to place said tank in fluid communication with the tanks of adjacent like tank cars while safely accommodating the relative motions between the adjacent tank cars in transit, whereby said tank may be connected to associated like tanks in a series through which fluid lading may flow to accommodate consecutive loading thereof while the position of said lading conduits adjacent to the top of said tank safely accommodates the relative motions between the adjacent tank cars in transit.
 2. The railway tank car set forth in claim 1, wherein the outer ends of said lading conduits respectively terminate inboard of the ends of said tank.
 3. A railway tank car adapted for interconnection in fluid communication with associated tank cars by flexible connecting conduits for accommodating consecutive loading, transporting and unloading of fluid ladings, said tank car comprising a wheeled chassis structure provided with chassis coupling means for coupling to the chassis of associated like cars, a tank mounted on said chassis structure, at least one lading conduit coupled to said tank adjacent to one end thereof in fluid communication therewith and extending outwardly therefrom adjacent to the top thereof, conduit coupling means on said lading conduit for coupling at the top of said tank to an adjacent end of an associated flexible connecting conduit to place said tank in fluid communication with the tank of an adjacent tank car while safely accommodating the relative motions between the adjacent tank cars in transit, and a loading and unloading assembly mounted on the bottom of said tank for connection to a source of lading for loading said tank and for connection to an outlet pipe for unloading said tank, whereby said tank may be connected to an associated tank as the end tank in a series through which fluid lading may flow to accommodate consecutive loading, transporting and unloading thereof while the position of said lading Conduits adjacent to the top of said tanks safely accommodates the relative motions between the adjacent tank cars in transit.
 4. A railway tank car for interconnection in fluid communication with associated like tank cars by flexible connecting conduits for accommodating consecutive loading of expandable liquid ladings, said tank car comprising a wheeled chassis structure provided with chassis coupling means for coupling to the chassis of associated like cars, a tank mounted on said chassis structure, a lading input conduit and a lading output conduit respectively coupled to said tank adjacent to the opposite ends thereof and being in fluid communication therewith, each of said lading conduits having an outer end extending outwardly from said tank adjacent to the top thereof, the inner end of said output conduit terminating a predetermined distance below the top of said tank, filling of said tank to a level above the inner end of said lading output conduit causing compression of gas trapped above said liquid lading to a pressure at which occurs outflow of liquid lading through said output conduit at the same rate of inflow of liquid lading through said input conduit thereby to provide in said tank above the liquid lading a free vapor space, and conduit coupling means on each of said lading conduits for coupling to an adjacent end of an associated flexible connecting conduit to place said tank in fluid communication with the tanks of adjacent like tank cars, whereby said tank may be connected by associated flexible connecting conduits to associated like tanks in a series through which expandable liquid lading may flow to accommodate consecutive loading to a predetermined level while automatically providing a free vapor space at the top of said tank above the liquid lading.
 5. The railway tank car set forth in claim 4, wherein the inner end of said lading output conduit is flared to permit an increased rate of loading of said tank.
 6. A railway tank car for interconnection in fluid communication with associated like tank cars by flexible connecting conduits for accommodating consecutive loading, transporting and unloading of expandable liquid ladings, said tank car comprising a wheeled chassis structure provided with chassis coupling means for coupling to the chassis of associated like cars, a tank mounted on said chassis structure, a lading vent conduit and a lading eduction conduit respectively coupled to said tank adjacent to the opposite ends thereof and being in fluid communication therewith, each of said lading conduits having an outer end extending outwardly from said tank adjacent to the top thereof, the inner end of said vent conduit terminating a predetermined distance below the top of said tank, filling of said tank to a level above the inner end of said vent conduit causing compression of gas trapped above said liquid lading to a pressure at which occurs outflow of liquid lading through said vent conduit at the same rate as the inflow of liquid lading through said eduction conduit thereby to provide in said tank above the liquid lading a free vapor space, the inner end of said eduction conduit terminating closely adjacent to the bottom of said tank to facilitate emptying of said tank through said eduction conduit, and conduit coupling means on each of said lading conduits for coupling to an adjacent end of an associated flexible connecting conduit to place said tank in fluid communication with the tanks of adjacent like tank cars, whereby said tank may be connected by associated flexible connecting conduits to associated like tanks in a series through which expandable liquid lading may flow to accommodate consecutive loading to a predetermined level, transporting thereof while automatically providing a free vapor space at the top of said tank above the liquid lading, and substantially complete unloading thereof through said eduction conduit.
 7. The railway tank car set forth in claim 6, wherein the inner end of said lading eduction conduit is flared to permit maximum unloading of said tank through said eduction conduit.
 8. A railway tank car for interconnection in fluid communication with associated tank cars by flexible connecting conduits for accommodating consecutive loading of expandable ladings, said tank car comprising a wheeled chassis structure provided with chassis coupling means for coupling to the chassis of associated cars, a tank mounted on said chassis structure, two lading conduits respectively coupled to said tank adjacent to the opposite ends thereof and being in fluid communication therewith, each of said lading conduits having an outer end extending outwardly from said tank adjacent to the top thereof and an inner end in communication with the interior of said tank, the inner end of one of said conduits extending into said tank and being adjustable toward and away from the top of said tank so as to terminate an adjustable predetermined distance below the top of said tank, filling of said tank to a level above the inner end of said one lading conduit causing compression of gas trapped above said liquid lading to a pressure at which occurs outflow of liquid lading through said output conduit at the same rate of inflow of liquid lading through said input conduit thereby to provide in said tank above the liquid lading a free vapor space, and conduit coupling means on each of said lading conduits for coupling to an adjacent end of an associated flexible connecting conduit to place said tank in fluid communication with the tanks of adjacent tank cars, whereby said tank may be connected by associated flexible connecting conduits to associated tanks in a series through which expandable liquid lading may flow to accommodate consecutive loading to a predetermined adjustable level while automatically providing an adjustable free vapor space at the top of said tank above the liquid lading.
 9. The railway tank car set forth in claim 8, wherein the position of the inner end of said one lading conduit can be adjusted from the exterior of said tank.
 10. The railway tank car set forth in claim 8, wherein the position of the inner end of said one lading conduit is adjustable from the interior of said tank.
 11. A railway tank car for interconnection in fluid communication with associated like tank cars by flexible connecting conduits for accommodating consecutive unloading of fluid ladings, said tank car comprising a wheeled chassis structure provided with chassis coupling means for coupling to the chassis of associated like cars, a tank mounted on said chassis structure, a lading input conduit and a lading output conduit respectively coupled to said tank adjacent to the opposite ends thereof and being in fluid communication therewith, each of said lading conduits having an outer end extending outwardly from said tank adjacent to the top thereof and an inner end extending into said tank, the inner end of said output conduit terminating closely adjacent to the bottom of said tank to facilitate emptying of said tank through said output conduit, and conduit coupling means on each of said lading conduits for coupling to an adjacent end of an associated flexible connecting conduit to place said tank in fluid communication with the tanks of adjacent like tank cars, whereby said tank may be connected by associated flexible connecting conduits to associated like tanks in a series through which fluid lading may flow to accommodate consecutive unloading thereof while the position of said lading conduits adjacent to the top of said tank safely accommodates the relative motions of the tank cars in transit.
 12. The railway tank car set forth in claim 11, and further including support means mounted on the inside of said tank adjacent to the bottom thereof and connected to said output conduit adjacent to the inner end thereof for effecting a rigid mounting thereof in said tank.
 13. A railway tank car train for accommodating consecutive loading of fluid ladings, said train comprising a plurality of railway tank cars connected In tandem relationship; each of said tank cars including wheeled chassis structure provided with chassis coupling means for coupling said cars together, a tank mounted on said chassis structure, two lading conduits respectively coupled to said tank adjacent to the opposite ends thereof in fluid communication therewith and each extending outwardly therefrom adjacent to the top thereof, and conduit coupling means at the outer end of each of said lading conduits; and a plurality of flexible connecting conduits respectively extending between adjacent coupled ones of said tank cars and coupled to said conduit coupling means thereon at the tops of said tanks, said flexible connecting conduits interconnecting said lading conduits to place said adjacent ones of said tanks in fluid communication with each other while safely accommodating the relative motions between said tank cars in transit, whereby said flexible connecting conduits cooperate with said tanks to form a continuous lading vessel through which fluid lading may flow to accommodate consecutive loading thereof while the position of said lading conduits adjacent to the tops of said tanks permits said flexible connecting conduits safely to accommodate the relative motions between adjacent ones of said tank cars in transit.
 14. The railway tank car train set forth in claim 13, wherein the inner end of one of said lading conduits of each of said tanks terminates closely adjacent to the bottom of said tank to facilitate emptying of said tanks therethrough.
 15. A railway tank car train for accommodating consecutive loading, transporting and unloading of fluid ladings, said train comprising a plurality of railway tank cars connected in tandem relationship; each of said tank cars including wheeled chassis structure provided with chassis coupling means for coupling said cars together, a tank mounted on said chassis structure, at least one lading conduit respectively coupled to the tanks of the end tank cars of said train and in fluid communication with the respective tank and each extending outwardly therefrom adjacent to the top thereof, two lading conduits respectively coupled to the tanks of the intermediate tank cars of said train adjacent to the opposite ends thereof and in fluid communication therewith and each extending outwardly therefrom adjacent to the top thereof, and conduit coupling means at the outer end of each of said lading conduits; a plurality of flexible connecting conduits respectively extending between adjacent coupled ones of said tank cars and coupled to said conduit coupling means thereon at the tops of said tanks, said fexible connecting conduits interconnecting said lading conduits to place said adjacent ones of said tanks in fluid communication with each other while safely accommodating the relative motions between said tank cars in transit, and a loading and unloading assembly mounted on the bottom of the tank of an end tank car of said train for connection to a source of lading for loading said train and for connection to an outlet pipe for unloading said train, whereby said flexible connecting conduits cooperate with said tanks to form a continuous lading vessel through which fluid lading may flow to accommodate consecutive loading, transporting and unloading thereof while the position of said lading conduits adjacent to the tops of said tanks permits said flexible connecting conduits safely to accommodate the relative motions between adjacent ones of said tank cars in transit.
 16. A railway tank car train for accommodating consecutive loading, transporting and unloading of expandable liquid ladings, said train comprising a plurality of railway tank cars connecting in tandem relationship; each of said tank cars comprising a wheeled chassis structure provided with chassis coupling means for coupling said cars together, a tank mounted on said chassis structure, a lading vent conduit and a lading eduction conduit respectively coupled to each of said tanks adjacent to the opposite ends theReof and being in fluid communication therewith, each of said lading conduits having an outer end extending outwardly from said tank adjacent to the top thereof, the inner end of said vent conduit terminating a predetermined distance below the top of said tank, filling of said tank to a level above the inner end of said vent conduit causing compression of gas trapped above said liquid lading to a pressure at which occurs outflow of liquid lading through said vent conduit at substantially the same rate as the inflow of liquid lading through said eduction conduit thereby to provide in said tank above the liquid lading a free vapor space, the inner end of said eduction conduit terminating closely adjacent to the bottom of said tank to facilitate emptying of said tank through said eduction conduit, and conduit coupling means at the outer end of each of said lading conduits; a plurality of flexible connecting conduits respectively extending between adjacent coupled ones of said tank cars and coupled to said conduit coupling means thereon at the tops of said tanks, said flexible connecting conduits interconnecting said lading conduits to place the adjacent ones of said tanks in fluid communication with each other while safely accommodating the relative motions between the tank cars in transit, whereby said flexible connecting conduits cooperate with said tanks to form a continuous lading vessel through which expandable liquid lading may flow to accommodate consecutive loading to a predetermined level, transporting thereof while automatically providing a free vapor space at the top of each tank above the expandable liquid lading, and substantially complete unloading thereof through said eduction conduits, the position of said lading conduits adjacent to the tops of said tanks permitting said flexible connecting conduits safely to accommodate the relative motions between adjacent ones of said tank cars in transit.
 17. The railway tank car train set forth in claim 16, wherein the inner ends of said lading vent conduits and said lading eduction conduits are flared to permit an increased rate of loading and unloading of said tank car train.
 18. A railway tank car for interconnection in fluid communication with associated like tank cars by flexible connecting conduits for accommodating consecutive loading and transporting of fluid ladings, said tank car comprising a wheeled chassis structure provided with chassis coupling means for coupling to the chassis of associated like cars, a tank mounted on said chassis structure, two lading conduits respectively coupled to said tank adjacent to the opposite ends thereof in fluid communication therewith and each extending outwardly therefrom adjacent to the top thereof, conduit coupling means on each of said lading conduits for coupling to an adjacent end of an associated flexible connecting conduit to place said tank in fluid communication with the tanks of adjacent like tank cars, two valves respectively connected in said two lading conduits for controlling the flow of fluid lading therethrough, and automatic valve control mechanism coupled to each of said valves and actuatable from a single location to accommodate simultaneous operation of said valves, whereby said tank may be connected by associated flexible connecting conduits to associated like tanks in a series through which fluid lading may flow to accommodate consecutive loading and transporting thereof and with the valves of all cars in the series being controllable automatically from a single location.
 19. The railway tank car set forth in claim 18, wherein said valve control mechanism is pneumatically operated.
 20. The railway tank car set forth in claim 18, wherein each of said valves is movable between a closed condition and an open condition, each of said valves further including bias means resiliently urging said valve toward the closed condition thereof, said automatic valve control mechanism being operable for moving said valves to the open conditions thereof Against the urging of said bias means, whereby said valves will remain in the closed conditions thereof until said automatic valve control mechanism is actuated.
 21. The railway tank car set forth in claim 18, and further comprising strong means connecting said valves to said tank, and wherein the connection between said valves and the portion of said lading conduits in said tank is substantially mechanically stronger than the connection between said valves and the outer portions of said conduit coupling means, whereby the connection between said conduit coupling means and said valves will break before the connection between said valves and said lading conduits thus to insure that the valves remain connected to said lading conduits in the event of damage to said railway tank car.
 22. The railway tank car set forth in claim 18, and further including a valve position indicator for each of said valves mounted exteriorly thereof and visible from the exterior of said tank car and movable between a first position corresponding to the open condition of the associated valve and a second position corresponding to the closed condition of the associated valve.
 23. A railway tank car train which can be loaded and unloaded from a single location for accommodating consecutive loading and transporting of fluid ladings, said train comprising a plurality of railway tank cars connected in tandem relationship; each of said tank cars including wheeled chassis structure provided with chasis coupling means for coupling said cars together, a tank mounted on said chassis structure, and two lading conduits respectively coupled to said tank adjacent to the opposite ends thereof in fluid communication therewith and each extending outwardly therefrom adjacent to the top thereof, conduit coupling means at the outer end of each of said lading conduits, and two valves respectively connected in said two lading conduits for controlling the flow of liquid lading therethrough; automatic valve control mechanism coupled to each of said valves on each said tank car and actuatable from a single location to accommodate essentially simultaneous operation of said valves; and a plurality of flexible connecting conduits respectively extending between adjacent coupled ones of said tank cars and interconnecting the outer ends of said lading conduits to place said adjacent ones of said tank cars in fluid communication with each other; whereby said flexible connecting conduits cooperate with said tanks to form a continuous lading vessel through which fluid lading may flow to accommodate consecutive loading and transporting thereof and with the valves of all of said tanks being controllable automatically from a common location.
 24. The railway tank car train set forth in claim 23, wherein a plurality of common locations is provided along said train for controlling automatically the valves of all of said tanks.
 25. A railway tank car for interconnection in fluid communication with associated like tank cars by flexible connecting conduits for accommodating consecutive loading, transporting and unloading of fluid ladings, said tank car comprising a wheeled chassis structure provided with chassis coupling means for coupling to the chassis of associated like cars, a tank mounted on said chassis structure, a main lading conduit disposed above said tank and extending longitudinally thereof substantially the entire length thereof, two branch lading conduits communicating with said main conduit and being respectively coupled to said tank adjacent to the opposite ends thereof and being in fluid communication therewith, a valve assembly connected in said main conduit intermediate said two branch conduits, said valve assembly having an open condition permitting passage of fluid lading through said main conduit for connecting adjacent tank cars in parallel and accommodating parallel loading thereof, said valve assembly having a closed condition preventing passage of fluid lading through said main conduit for conneCting adjacent tank cars in series and accommodating serial loading thereof, and conduit coupling means at each of the opposite ends of said main lading conduit for coupling to one end of an associated flexible connecting conduit to place said tank in fluid communication with the tanks of adjacent like tank cars, whereby said tank may be connected by associated flexible connecting conduits to associated like tanks in a series to form a continuous lading vessel accommodating serial or parallel loading thereof depending upon the condition of said valve assembly.
 26. A railway tank car train which can be loaded and unloaded from a single location for accommodating consecutive loading, transporting and unloading of fluid ladings, said train comprising a plurality of railway tank cars connected in tandem relationship; each of said tank cars including wheeled chassis structure provided with chassis coupling means for coupling said cars together, a tank mounted on said chassis structure, and a main lading conduit disposed above said tank and extending longitudinally thereof substantially the entire length thereof, two branch lading conduits communicating with said main conduit and being respectively coupled to said tank adjacent to the opposite ends thereof and being in fluid communication therewith, conduit coupling means at each end of said main lading conduit, and a valve assembly connected in said main conduit intermediate said two branch conduits, said valve assembly having an open condition permitting passage of fluid lading through said main conduit for connecting adjacent tank cars in parallel and accommodating simultaneous loading thereof, said valve assembly having a closed condition preventing passage of fluid lading through said main conduit for connecting adjacent tank cars is series and accommodating serial loading thereof; and a plurality of flexible connecting conduits respectively extending between adjacent coupled ones of said tank cars and interconnecting the ends of said main lading conduits to place said adjacent ones of said tank cars in fluid communication with each other; whereby said flexible connecting conduits cooperate with said tanks to form a continuous lading vessel through which fluid lading may flow to accommodate serial or parallel loading thereof depending upon the condition of said valve assembly.
 27. A railway tank car for interconnection in fluid communication with associated like tank cars by flexible connection conduits for accommodating consecutive loading, transporting and unloading of fluid ladings, said tank car comprising a wheeled chassis structure provided with chassis coupling means movable between a coupling condition for coupling to the chassis of associated like cars and an uncoupling condition, a coupling control member mounted on said chassis and connected to said chassis coupling means and movable from a coupling configuration to an uncoupling configuration for effecting movement of said chassis coupling means from the coupled condition thereof to the uncoupled condition thereof, lock mechanism engageable with said coupling control member in the coupling configuration thereof for preventing movement thereof to the uncoupling configuration thereof, a tank mounted on said chassis structure, two lading conduits coupled to said tank and being in fluid communication therewith, conduit coupling means on each of said lading conduits for coupling to an adjacent end of an associated flexible connecting conduit to place said tank in fluid communication with the tanks of adjacent like tank cars, whereby said tank may be connected by associated flexible connecting conduits to associated like tanks in a series through which fluid lading may flow to accommodate consecutive loading, transporting and unloading thereof while accidental uncoupling of adjacent cars in the series is prevented.
 28. The railway tank car set forth in claim 27, wherein said lock mechanism includes a pin movable between a locking position for engagement With said coupling control member in the coupling configuration thereof to prevent movement thereof to the uncoupling configuration thereof and an unlocking position accommodating movement of said coupling control member between the coupling and uncoupling configurations thereof.
 29. A railway tank car train for accommodating consecutive loading, transporting and unloading of fluid ladings, said train comprising a plurality of railway tank cars connected in tandem relationship; each of said tank cars including wheeled chassis structure provided with chassis coupling means movable between a coupling condition for coupling to the chassis of adjacent cars and an uncoupling condition, a coupling control member mounted on said chassis and connected to said chassis coupling means and movable from a coupling configuration to an uncoupling configuration for effecting movement of said chassis coupling means from the coupled condition thereof to the uncoupled condition thereof, lock mechanism engageable with said coupling control member in the coupling configuration thereof for preventing movement thereof to the uncoupling configuration thereof, a tank mounted on said chassis structure, two lading conduits coupled to said tank and being in fluid communication therewith, and conduit coupling means at the outer end of each of said lading conduits; and a plurality of flexible connecting conduits respectively extending between adjacent coupled ones of said tank cars and coupled to said conduit coupling means thereon interconnecting said lading conduits to place said adjacent ones of said tank cars in fluid communication with each other; whereby said flexible connecting conduits cooperate with said tanks to form a continuous lading vessel through which fluid lading may flow to accommodate consecutive loading, transporting and unloading thereof while accidental uncoupling of adjacent cars is prevented.
 30. A railway tank car for interconnection in fluid communication with associated like tank cars by flexible connecting conduits for accommodating consecutive loading and transporting of fluid ladings, said tank car comprising a wheeled chassis structure provided with chassis coupling means for coupling to the chassis of associated like cars, a tank mounted on said chassis structure, two lading conduits coupled to said tank in fluid communication therewith and extending outwardly therefrom adjacent to the top thereof, two valves mounted on said tank externally thereof and respectively connected in said two lading conduits for controlling the flow of liquid lading through said lading conduits, and conduit coupling means respectively connected to each of said valves by a breakaway connection for coupling to one end of an associated flexible connecting conduit to place said tank in fluid communication with the tanks of adjacent like tank cars, whereby said tank may be connected by associated flexible connecting conduits to associated like tanks in a series through which fluid lading may flow to accommodate consecutive loading and transporting thereof while said external valves are protected against damage in transit.
 31. The railway tank car set forth in claim 30, wherein said two valves have a low profile, thereby further to protect said valves against damage in transit.
 32. The railway tank car set forth in claim 30, and further comprising two discrete housings respectively surrounding said two valves.
 33. The railway tank car set forth in claim 32, wherein each of said housings includes a pair of upstanding heavy duty guard plates rigidly mounted on said tank externally thereof, said guard plates being respectively disposed closely adjacent to the opposite ends of the associated valve and extending transversely of said tank substantially parallel to each other, and a box-like rigid outer covering cooperating with said tank and said guard plates substantially to surround the associated valve.
 34. A railway tank car for interconnection to fluid communication with associated liKe tank cars by flexible connecting conduits for accommodating consecutive loading and transporting of fluid ladings, said tank car comprising a wheeled chassis structure provided with chassis coupling means for coupling to the chassis of associated like cars, a tank mounted on said chassis structure, two lading conduits respectively coupled to said tank adjacent to the opposite ends thereof in fluid communication therewith and each extending outwardly therefrom adjacent to the top thereof, conduit coupling means on each of said lading conduits for coupling to an adjacent end of an associated flexible connecting conduit to place said tank in fluid communication with the tanks of adjacent like tank cars, two valves respectively connected in said two lading conduits for controlling the flow of fluid lading therethrough, and automatic valve control mechanism coupled to each of said valves and actuatable from a single location to accommodate simultaneous operation of said valves, said valves and said valve control mechanism being fail-safe in operation whereby upon failure or deactivation of said valve control mechanism said valves move to the closed positions thereof, whereby said tank may be connected by associated flexible connecting conduits to associated like tanks in a series through which fluid lading may flow to accommodate consecutive loading and transporting thereof and with the valves of all cars in the series being controllable automatically from a single location.
 35. A railway tank car adapted for interconnection in fluid communication with associated like tank cars by flexible connecting conduits for accommodating consecutive loading of fluid ladings, said tank car comprising a wheeled chassis structure provided with chassis coupling means for coupling to the chassis of associated like cars, a tank mounted on said chassis structure, two lading conduits respectively coupled to said tank adjacent to the opposite ends thereof in fluid communication therewith and each extending outwardly therefrom adjacent to the top thereof, a flexible hose for at least one of said lading conduits, and conduit coupling means on each of said lading conduits for coupling at the top of said tank to the adjacent end of said flexible hose to place said tank in fluid communication with the tanks of adjacent like tank cars, said flexible hose safely accommodating the relative motions between the adjacent tank cars in transit while maintaining a fluidtight connection therefor, whereby said tank may be connected to associated like tanks in a series through which fluid lading may flow to accommodate consecutive loading thereof while the position of said lading conduits adjacent to the top of said tank safely accommodates the relative motions between the adjacent tank cars in transit.
 36. A railway tank car adapted for interconnection in fluid communication with associated like tank cars by flexible connecting conduits for accommodating consecutive loading of fluid ladings, said tank car comprising a wheeled chassis structure provided with chassis coupling means for coupling to the chassis of associated like cars, a tank mounted on said chassis structure, two lading conduits respectively coupled to said tank adjacent to the opposite ends thereof in fluid communication therewith and each extending outwardly therefrom adjacent to the top thereof, a flexible hose for at least one of said lading conduits, conduit coupling means on each of said lading conduits for coupling at the top of said tank to the adjacent end of a flexible hose to place said tank in fluid communication with tanks of adjacent like tank cars, and a support for said flexible hose mounted on the adjacent end of said tank car for maintaining said flexible hose at an elevation higher than that of the associated conduit coupling means so as to cause drainage of all the lading from said flexible hose through the associated conduit coupling means and into said tank, said flexible hose safely accommodating the relative motions beTween the adjacent tank cars in transit while maintaining a fluid-tight connection therefor, whereby said tank may be connected to associated like tanks in a series through which fluid lading may flow to accommodate consecutive loading thereof while the position of said lading conduits adjacent to the top of said tank safely accommodates the relative motions between the adjacent tank cars in transit.
 37. A railway tank car train for accommodating consecutive loading of fluid ladings, said train comprising a plurality of railway tank cars connected in tandem relationship; each of said tank cars including wheeled chassis structure provided with chassis coupling means for coupling said cars together, a tank mounted on said chassis structure, two lading conduits respectively coupled to said tank adjacent to the opposite ends thereof in fluid communication therewith and each extending outwardly therefrom adjacent to the top thereof, and conduit coupling means at the outer end of each of said lading conduits; and a plurality of flexible hoses respectively extending between adjacent coupled ones of said tank cars and coupled to said conduit coupling means thereon at the tops of said tanks to place said tanks in fluid communication with the tanks of adjacent tank cars, said flexible hoses safely accommodating the relative motions between the adjacent tank cars in transit while maintaining a fluid-tight connection therefor, whereby said flexible hoses cooperate with said tanks to form a continuous lading vessel through which fluid lading may flow to accommodate consecutive loading thereof while the position of said lading conduits adjacent to the tops of said tanks permits said flexible hoses safely to accommodate the relative motions between adjacent ones of said tank cars in transit.
 38. A railway tank car train for accommodating consecutive loading of fluid ladings, said train comprising a plurality of railway tank cars connected in tandem relationship; each of said tank cars including wheeled chassis structure provided with chassis coupling means for coupling said cars together, a tank mounted on said chassis structure, two lading conduits respectively coupled to said tank adjacent to the opposite ends thereof in fluid communication therewith and each extending outwardly therefrom adjacent to the top thereof, and conduit coupling means at the outer end of each of said lading conduits; and a plurality of flexible hoses respectively extending between adjacent coupled ones of said tank cars and coupled to said conduit coupling means thereon at the tops of said tanks to place said tanks in fluid communication with the tanks of adjacent tank cars, and supports for said flexible hoses respectively mounted on the adjacent ends of said tank cars for maintaining said flexible hoses at an elevation higher than that of the associated conduit coupling means so as to cause drainage of all the lading from said flexible hoses through the associated coupling means and into the associated tanks, said flexible hoses safely accommodating the relative motions between the adjacent tank cars in transit while maintaining a fluid-tight connection therefor, whereby said flexible hoses cooperate with said tanks to form a continuous lading vessel through which lading may flow to accommodate consecutive loading thereof while the position of said lading conduits adjacent to the tops of said tanks permits said flexible hoses safely to accommodate the relative motions between adjacent ones of said tank cars in transit.
 39. A railway tank car adapted for interconnection in fluid communication with associated like tank cars by flexible connecting conduits for accommodating consecutive loading of fluid ladings, said tank car comprising a wheeled chassis structure provided with chassis coupling means for coupling to the chassis of associated like cars, a tank mounted on said chassis structure, two lading conduits respectively coupled to said tank adjacent to the opposite ends thereof in fluid communication thereWith and each extending outwardly therefrom adjacent to the top thereof, conduit coupling means on each of said lading conduits for coupling at the top of said tank to an adjacent end of an associated flexible connecting conduit to place said tank in fluid communication with the tanks of adjacent like tank cars while safely accommodating the relative motions between the adjacent tank cars in transit, and a fluid level detecting means mounted on said tank adjacent to the top thereof and extending downwardly thereinto for sensing the fluid lading when it reaches the desired level in said tank, whereby said tank may be connected to associated like tanks in a series through which fluid lading may flow to accommodate consecutive loading thereof while the position of said lading conduits adjacent to the top of said tank safely accommodates the relative motions between the adjacent tank cars in transit.
 40. The railway tank car set forth in claim 39, wherein said fluid level detecting means is electrically operated and is connectable to the pumping system for filling said tank car to interrupt operation thereof when the fluid lading reaches the desired level in said tank.
 41. A railway tank car train for accommodating consecutive loading, transporting and unloading of fluid ladings, said train comprising a plurality of railway tank cars connected in tandem relationship; each of said tank cars including wheeled chassis structure provided with chassis coupling means for coupling said cars together, a tank mounted on said chassis structure, at least one lading conduit respectively coupled to the tanks of the end tank cars of said train and in fluid communication with the respective tank and each extending outwardly therefrom adjacent to the top thereof, two lading conduits respectively coupled to the tanks of the intermediate tank cars of said train adjacent to the opposite ends thereof and in fluid communication therewith and each extending outwardly therefrom adjacent to the top thereof, and conduit coupling means at the outer end of each of said lading conduits; a plurality of flexible hoses respectively extending between adjacent coupled ones of said tank cars and coupled to said conduit coupling means thereon at the tops of said tanks, said flexible hoses interconnecting said lading conduits to place said adjacent ones of said tanks in fluid communication with each other, supports for said flexible hoses mounted on adjacent ends of said tank cars for maintaining said flexible hoses at an elevation higher than that of an associated conduit coupling means, and means for connecting the lading conduit through which said train of cars is filled to a source of pressure higher than that to which is connected the lading conduit at the other ends of said train of cars, so that the pressure differential will force the fluid lading from said flexible hoses from the input ends to the other ends thereof, whereby said flexible hoses cooperate with said tanks to form a continuous lading vessel through which fluid lading may flow to accommodate consecutive loading, transporting and unloading thereof while the position of said lading conduits adjacent to the tops of said tanks and the supports for said flexible hoses permits said flexible hoses safely to accommodate the relative motions between adjacent ones of said tank cars in transit.
 42. The railway tank car train set forth in claim 41, wherein subsequent to loading thereof the lading conduit at the inlet ends of said train is adapted to be connected to a source of pressure above atmospheric pressure and the lading conduit at the other end of said train is adapted to be connected to atmospheric pressure.
 43. The railway tank car train set forth in claim 41, wherein subsequent to loading thereof the lading conduit at the inlet end of said train is adapted to be connected to atmospheric pressure and the lading conduit at the other end of said train is adapted to be connected to a source of pressure below atmospheric pressure.
 44. A railway tank car for interconnection in fluid communication with associated like tank cars by flexible connecting conduits for accommodating consecutive loading, transporting and unloading of fluid ladings, said tank car comprising a wheeled chassis structure provided with chassis coupling means for coupling to the chassis of associated like cars, a tank mounted on said chassis structure, a main lading conduit disposed above said tank and extending longitudinally thereof substantially the entire length thereof, two branch lading conduits communicating with said main conduit and being respectively coupled to said tank adjacent to the opposite ends thereof and being in fluid communication therewith, a valve assembly connected in said main conduit intermediate said two branch conduits, said valve assembly having an open condition permitting passage of fluid lading through said main conduit for connecting adjacent tank cars in parallel and accommodating parallel loading thereof, said valve assembly having a closed condition preventing passage of fluid lading through said main conduit for connecting adjacent tank cars in series and accommodating serial loading thereof, conduit coupling means at each of the opposite ends of said main lading conduit for coupling to one end of an associated flexible connecting conduit to place said tank in fluid communication with the tanks of adjacent like tank cars, a vent line disposed above said tank and extending longitudinally thereof substantially the entire length thereof and having a connection in fluid communication with said tank, connecting means connecting said vent line to vent lines on adjacent cars to provide a continuous vent line for venting said tank during loading and unloading thereof, whereby said tank may be connected by associated flexible connecting conduits to associated like tanks in a series to form a continuous lading vessel accommodating serial or parallel loading thereof depending upon the condition of said valve assembly.
 45. The railway tank car set forth in claim 44, and further comprising a check valve within said tank in the connection to said vent line in fluid communication with said tank, said check valve closing automatically when the lading in the tank reaches the proper level during loading.
 46. A railway tank car train which can be loaded and unloaded from a single location for accommodating consecutive loading, transporting and unloading of fluid ladings, said train comprising a plurality of railway tank cars connected in tandem relationship; each of said tank cars including wheeled chassis structure provided with chassis coupling means for coupling said cars together, a tank mounted on said chassis structure, and a main lading conduit disposed above said tank and extending longitudinally thereof substantially the entire length thereof, two branch lading conduits communicating with said main conduit and being respectively coupled to said tank adjacent to the opposite ends thereof and being in fluid communication therewith, conduit coupling means at each end of said main lading conduit, and a valve assembly connected in said main conduit intermediate said two branch conduits, said valve assembly having an open condition permitting passage of fluid lading through said main conduit for connecting adjacent tank cars in parallel and accommodating simultaneous loading thereof, said valve assembly having a closed condition preventing passage of fluid lading through said main conduit for connecting adjacent tank cars in series and accommodating serial loading thereof; and a plurality of flexible connecting conduits respectively extending between adjacent coupled ones of said tank cars and interconnecting the ends of said main lading conduits to place said adjacent ones of said tank cars in fluid communication with each other; a vent line disposed above said tank and extending longitudinally thereof substantially the entire length thereof and having a connection in fluid communication with said tank, a pluRality of flexible connections respectively extending between said vent lines to place said vent lines in fluid communication with each other to provide a continuous vent line through which said tanks can be vented during loading and unloading of said tanks; whereby said flexible connecting conduits cooperate with said tanks to form a continuous lading vessel through which fluid lading may flow to accommodate serial or parallel loading thereof depending upon the condition of said valve assembly.
 47. The railway tank car train set forth in claim 46 and further comprising a check valve within each tank in the connection to said vent line in fluid communication with said tank, said check valve closing automatically when the lading in the tank reaches the proper level during loading.
 48. A railway tank car train for accommodating consecutive loading, transporting and unloading of fluid ladings, said train comprising a plurality of railway tank cars connected in tandem relationship; each of said tank cars including wheeled chassis structure provided with chassis coupling means for coupling said cars together, a tank mounted on said chassis structure, at least one lading conduit respectively coupled to the tanks of the end tank cars of said train and in fluid communication with the respective tank and each extending outwardly therefrom adjacent to the top thereof, two lading conduits respectively coupled to the tanks of the intermediate tank cars of said train adjacent to the opposite ends thereof and in fluid communication therewith and each extending outwardly therefrom adjacent to the top thereof, and conduit coupling means at the outer end of each of said lading conduits; a plurality of flexible hoses respectively extending between adjacent coupled ones of said tank cars and coupled to said conduit coupling means thereon at the tops of said tanks, said flexible hoses interconnecting said lading conduits to place said adjacent ones of said tanks in fluid communication with each other, fluid level detecting means mounted on the tank of the end tank car of said train opposite from the end tank car through which fluid lading is to be loaded, said fluid level detecting means being mounted adjacent to the top of the associated tank and extending downwardly thereinto for sensing the fluid lading when it reaches the desired level in the associated tank, said fluid level detecting means being adjusted to accommodate the flow into the associated tank of the fluid lading from all of the flexible hoses in said train, whereby said flexible hoses cooperate with said tanks to form a continuous lading vessel through which fluid lading may flow to accommodate consecutive loading, transporting and unloading thereof while the position of said lading conduits adjacent to the tops of said tanks and the supports for said flexible hoses permits said flexible hoses safely to accommodate the relative motions between adjacent ones of said tank cars in transit. 